Audi 80/Avant (B4)

since 1991-1995 release

Repair and operation of the car

As the special equipment Audi offers system of self-examination. She watches eight functions, or operational sostoyany, after inclusion of ignition and after inclusion of a passing beam or a brake signal. Active control is exercised and during the movement. Thereby the system of autocheck replaces a number of the ordinary indicators which are available in standard option.

Indicators of malfunctions, which board is in the middle of a combination of devices, are divided into Danger Signal and Prevention Signal groups.

The malfunctions which significantly are influencing traffic safety or having the consequence serious damages are considered dangerous and therefore signals light up in the red color. These are the following signals:

• Brake system: too low level of brake fluid.
• Pressure of engine oil: oil pressure in the mode of idling falls lower than 0,3 bars, or with a frequency of rotation exceeding 2100 rpm indicators of 1,8 bars (model with 4-and 5-cylinder engines) or 2,5 bars are not reached (models with 6-cylinder engines).
• Cooling liquid: temperature of cooling liquid rises above 120 °C, or the working temperature, or too low level of the cooling means is not reached.
  In addition to a light signal of danger from a combination of devices the triple buzzer proceeds. Signals of danger have in system a priority before safety signals. Until there is a danger signal, the warning signal is suppressed. It appears only after elimination of the reason of a signal of danger.
  Warning signals are highlighted on the panel in the yellow color and are followed by a single buzzer. These are the following signals:
• Stoplight: this symbol appears right after ignition inclusion. If to press a brake pedal, the symbol disappears – provided that both brake lamps function.
• Lighting: the system of self-examination cannot execute this test stage completely automatically. At first the driver has to turn on a passing beam. The passing beam and back dimensions are at the same time controlled. The system is not able to show simultaneous refusal of both filaments of a passing beam or back dimensions, but generally this malfunction can hardly occur.
• Battery: the symbol of the battery flashes if accumulator tension goes beyond standard indicators of 10,6 — 15,6 Century.
• System of washing of glasses: this indicator indicates too low level of the washing liquid in a tank.
• Fuel tank: the symbol of gas station lights up if in a fuel tank there are only 12 l of gasoline.
  If on a board of warning signals there are some malfunctions, warning signals flash in turn, at ignition inclusion.
• The signal "OK" has to appear if after inclusion of ignition and pressing a pedal of a brake the inscription of "Bremslicht" (stoplight) went out. "OK" in this case means that all stages of check were passed without messages on malfunctions. Later short time the signal dies away.

Devices by determination of serviceability of lamps

These devices work at the electromagnetic principle and compare the current passing in conducting, for example, to the left and right passing beam. If in any wire because of a gap or defect of a lamp is not present a current expense, the control device establishes a difference and reports about it to the control unit. In case of malfunction of both lamps that occurs very seldom, naturally, it is also not noted differences. In this case the control device is not able to establish malfunction.

Removal of the control module

The control unit of system of autocheck is screwed on a reverse side of a combination of devices in one case with the block of indicators. You will find the description of removal of the module of system of autocheck at the beginning of this chapter in the section "Dismantling".

Search of malfunctions of system of self-examination

Control of system of self-examination in house conditions is possible only partially: at first it is necessary to check all sensors – if here malfunction was not found, so it should be looked for in the module of system of self-examination.

Independent control of the block of indicators

Additional functions on a board of system of self-examination

Warning of speed: after record of speed of the movement at present of time (pressing of the left button combinations of devices at a desirable speed) the system of autocheck indicates essential excess of this speed by emergence of a symbol and a buzzer. This record remains up to ignition switching off in case other speed of the movement was not written down or memory is erased (to hold the extreme left button pressed within a second).

Indicator of radio frequencies: if the field of indicators is not occupied with information from system of self-examination, on it there are data on the frequency of radio stations on the autoradio tape recorders equipped as appropriate. In addition the board of indicators informs on stereoreception or the enclosed cartridge (Tape). If radio stations transmit also signals of system of radio data, in the field of indicators there is an inscription of "RDS". Then on the radio display it is possible to read the name of radio station.